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Magnesium

Magnesium is a dietary mineral. Magnesium deficiencies is common in developed countries, and is often caused by diabetes and other conditions. A lack of magnesium will raise blood pressure and reduce insulin sensitivity.

Our evidence-based analysis on magnesium features 414 unique references to scientific papers.

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Summary of Magnesium

Primary information, health benefits, side effects, usage, and other important details

Magnesium is an essential dietary mineral, and the second most prevalent electrolyte in the human body. Magnesium deficiencies are common in developed countries. A deficiency increases blood pressure, reduces glucose tolerance and causes neural excitation.

Magnesium deficiencies are common in the western diet because grains are poor sources of magnesium. Other prominent sources of magnesium, like nuts and leafy vegetables, are not eaten as often. It is possible to fix a magnesium deficiency through dietary changes. If magnesium is supplemented to attenuate a deficiency, it acts as a sedative, reducing blood pressure and improving insulin sensitivity.

Maintaining healthy magnesium levels is also associated with a protective effect against depression and ADHD. Supplementation of magnesium is not very effective at reducing fat mass or cramps. Further evidence is needed to determine if magnesium supplementation can boost exercise performance, but initial results do not look promising.

The intestinal absorption of magnesium varies depending on how much magnesium the body needs, so there are not very many side-effects associated with supplementation. If there is too much magnesium, the body will only absorb as much as it needs. However, excessive doses may cause gastrointestinal distress and diarrhea.

📝 Want a quick summary of magnesium's potential benefits?

We've analyzed over 100 studies to summarize the research on magnesium's potential health benefits.

How to Take

Medical Disclaimer

Recommended dosage, active amounts, other details

The standard dose for magnesium supplementation is 200-400mg.

Any form of magnesium can be used to attenuate a magnesium deficiency, except magnesium L-threonate, since it contains less elemental magnesium per dose. Gastrointestinal side-effects, like diarrhea and bloating, are more common when magnesium oxide or magnesium chloride are supplemented, due to the lower absorption rates of these two forms. In general, magnesium citrate is a good choice for supplementation. Magnesium L-threonate can be used for cognitive enhancement.

Magnesium should be taken daily, with food.

Superloading magnesium, or taking more magnesium that is needed to attenuate a deficiency, should be done with magnesium diglycinate or magnesium gluconate.

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Human Effect Matrix

Unlocked for Examine members

The Human Effect Matrix summarizes human studies to tell you what effects Magnesium has on your body, how much evidence there is, and how strong these effects are.

Full details are available to Examine members.
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-b Notable Moderate See all 9 studies
There appears to be a significant reduction in blood pressure assuming one of two conditions is met, either the subject is low in magnesium levels in the body (deficient) or if the subject has elevated blood pressure (140/90 or above), with the latter not requiring a deficiency to precede the blood pressure reducing effects
grade-b Notable High See all 6 studies
Has the capacity to increase serum magnesium stores, but this is somewhat unreliable and may be dependent on the person being deficient in magnesium prior to supplementation
grade-b Minor High See all 4 studies
There appears to be a reduction in asthmatic symptoms associated with magnesium supplementation to a low degree, with the one study using corticosteroids alongside magnesium finding no effect. There may be a role for magnesium in aiding untreated asthma, but already medicated situations are not certain
grade-b Minor Moderate See all 8 studies
There appears to be some reduction in blood glucose in diabetics and persons with elevated glucose with magnesium supplementation, which may be secondary to better insulin functioning from the pancreas. The reduction in glucose is not overly impressive and is somewhat unreliable, and increases in glucose have been noted to occur during exercise when magnesium is supplemented in healthy persons
grade-b Minor Low See all 3 studies
More evidence than not suggest no significant effect on HbA1c levels, but one study suggests a decent decrease with the other two studies trending towards a decrease. There may be a role for magnesium in reducing HbA1c levels to a minor degree
grade-b Minor Moderate See all 6 studies
Decreases in fasting insulin appear to occur over long term supplementation with magnesium in persons at risk for diabetes or already with the disease state; decreases in insulin may not occur in normoglycemic persons
grade-b Minor High See all 4 studies
There appears to be increases in insulin sensitivity as assessed by HOMA-IR, which is thought to be secondary to aiding pancreatic function
grade-b - High See all 4 studies
For the most part, there is no significant direct influence of magnesium on HDL-C levels. Some counter evidence suggests it may occur vicariously through betterment of glycemic control in diabetics, but that is not always seen
grade-b - Very High See all 6 studies
For the most part, no significant influence of magnesium supplementation on triglycerides
grade-b - Very High See all 4 studies
No evidence to support a role for magnesium in inducing alterations in body weight
grade-c Notable - See study
The one study to assess aerobic exercise capacity noted a significant improvement during extreme physical stress (triathletes), which is notable and needs replication
grade-c Notable - See study
The one study to measure muscle oxygenation in high intensity exercise noted quite a remarkable increase in oxygenation in healthy athletes; this needs to be replicated
grade-c Minor - See study
An increase in bone mineral density has been noted with magnesium supplementation
grade-c Minor Moderate See 2 studies
Possible reduction in C-Reactive protein, but these changes are unreliable
grade-c Minor - See study
One study has noted a reduction in symptoms of migraines associated with oral magnesium supplementation
grade-c Minor Moderate See 2 studies
Possible but unreliable increases in osteocalcin
grade-c Minor Very High See all 5 studies
A moderate reduction in symptoms of PMS has been noted with magnesium supplementation in most trials, though evidence quality tends to be low and it's difficult to have great confidence in the results. One study found an apparent additive effect of magnesium and vitamin B6.
grade-c Minor Very High See 2 studies
An improvement in sleep quality has been noted in persons with poor sleep quality, no studies assess persons with normal sleep function
grade-c Minor - See study
A reduction in symptoms associated with diabetic neuropathy has been noted with magnesium supplementation
grade-c - - See study
No significant influence on cortisol seen with magnesium supplementation
grade-c - - See study
No evidence to support a reduction in pregnancy related leg cramps
grade-c - Very High See 2 studies
No significant influence on LDL cholesterol levels seen with magnesium supplementation
grade-c - Very High See 2 studies
No significant influences on testosterone levels noted with magnesium intake
grade-c - Very High See 2 studies
No significant influence on total cholesterol levels seen with magnesium supplementation
grade-d Minor Very High See 2 studies
Reduced depressive symptoms have been found in elderly diabetics
grade-d Minor - See study
Decreased symptoms associated with tinnitus have been noted following magnesium supplementation
grade-d - - See study
grade-d - - See study
No significant influence on oxidation rates of LDL cholesterol

Studies Excluded from Consideration

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Things to Note

Primary Function:

Do Not Confuse With

Manganese

Goes Well With

  • Magnesium is typically non-stimulatory. If deficient, high acute doses of supplemental magnesium can be slightly sedative.

📝 Want a quick summary of magnesium's potential benefits?

We've analyzed over 100 studies to summarize the research on magnesium's potential health benefits.

Click here to see all 414 references.